diff options
Diffstat (limited to 'drivers/leds/led-class.c')
-rw-r--r-- | drivers/leds/led-class.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c new file mode 100644 index 000000000000..0292df4101ba --- /dev/null +++ b/drivers/leds/led-class.c | |||
@@ -0,0 +1,147 @@ | |||
1 | /* | ||
2 | * LED Class Core | ||
3 | * | ||
4 | * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu> | ||
5 | * Copyright (C) 2005-2006 Richard Purdie <rpurdie@openedhand.com> | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify | ||
8 | * it under the terms of the GNU General Public License version 2 as | ||
9 | * published by the Free Software Foundation. | ||
10 | */ | ||
11 | |||
12 | #include <linux/config.h> | ||
13 | #include <linux/module.h> | ||
14 | #include <linux/kernel.h> | ||
15 | #include <linux/init.h> | ||
16 | #include <linux/list.h> | ||
17 | #include <linux/spinlock.h> | ||
18 | #include <linux/device.h> | ||
19 | #include <linux/sysdev.h> | ||
20 | #include <linux/timer.h> | ||
21 | #include <linux/err.h> | ||
22 | #include <linux/leds.h> | ||
23 | #include "leds.h" | ||
24 | |||
25 | static struct class *leds_class; | ||
26 | |||
27 | static ssize_t led_brightness_show(struct class_device *dev, char *buf) | ||
28 | { | ||
29 | struct led_classdev *led_cdev = class_get_devdata(dev); | ||
30 | ssize_t ret = 0; | ||
31 | |||
32 | /* no lock needed for this */ | ||
33 | sprintf(buf, "%u\n", led_cdev->brightness); | ||
34 | ret = strlen(buf) + 1; | ||
35 | |||
36 | return ret; | ||
37 | } | ||
38 | |||
39 | static ssize_t led_brightness_store(struct class_device *dev, | ||
40 | const char *buf, size_t size) | ||
41 | { | ||
42 | struct led_classdev *led_cdev = class_get_devdata(dev); | ||
43 | ssize_t ret = -EINVAL; | ||
44 | char *after; | ||
45 | unsigned long state = simple_strtoul(buf, &after, 10); | ||
46 | |||
47 | if (after - buf > 0) { | ||
48 | ret = after - buf; | ||
49 | led_set_brightness(led_cdev, state); | ||
50 | } | ||
51 | |||
52 | return ret; | ||
53 | } | ||
54 | |||
55 | static CLASS_DEVICE_ATTR(brightness, 0644, led_brightness_show, | ||
56 | led_brightness_store); | ||
57 | |||
58 | /** | ||
59 | * led_classdev_suspend - suspend an led_classdev. | ||
60 | * @led_cdev: the led_classdev to suspend. | ||
61 | */ | ||
62 | void led_classdev_suspend(struct led_classdev *led_cdev) | ||
63 | { | ||
64 | led_cdev->flags |= LED_SUSPENDED; | ||
65 | led_cdev->brightness_set(led_cdev, 0); | ||
66 | } | ||
67 | EXPORT_SYMBOL_GPL(led_classdev_suspend); | ||
68 | |||
69 | /** | ||
70 | * led_classdev_resume - resume an led_classdev. | ||
71 | * @led_cdev: the led_classdev to resume. | ||
72 | */ | ||
73 | void led_classdev_resume(struct led_classdev *led_cdev) | ||
74 | { | ||
75 | led_cdev->brightness_set(led_cdev, led_cdev->brightness); | ||
76 | led_cdev->flags &= ~LED_SUSPENDED; | ||
77 | } | ||
78 | EXPORT_SYMBOL_GPL(led_classdev_resume); | ||
79 | |||
80 | /** | ||
81 | * led_classdev_register - register a new object of led_classdev class. | ||
82 | * @dev: The device to register. | ||
83 | * @led_cdev: the led_classdev structure for this device. | ||
84 | */ | ||
85 | int led_classdev_register(struct device *parent, struct led_classdev *led_cdev) | ||
86 | { | ||
87 | led_cdev->class_dev = class_device_create(leds_class, NULL, 0, | ||
88 | parent, "%s", led_cdev->name); | ||
89 | if (unlikely(IS_ERR(led_cdev->class_dev))) | ||
90 | return PTR_ERR(led_cdev->class_dev); | ||
91 | |||
92 | class_set_devdata(led_cdev->class_dev, led_cdev); | ||
93 | |||
94 | /* register the attributes */ | ||
95 | class_device_create_file(led_cdev->class_dev, | ||
96 | &class_device_attr_brightness); | ||
97 | |||
98 | /* add to the list of leds */ | ||
99 | write_lock(&leds_list_lock); | ||
100 | list_add_tail(&led_cdev->node, &leds_list); | ||
101 | write_unlock(&leds_list_lock); | ||
102 | |||
103 | printk(KERN_INFO "Registered led device: %s\n", | ||
104 | led_cdev->class_dev->class_id); | ||
105 | |||
106 | return 0; | ||
107 | } | ||
108 | EXPORT_SYMBOL_GPL(led_classdev_register); | ||
109 | |||
110 | /** | ||
111 | * led_classdev_unregister - unregisters a object of led_properties class. | ||
112 | * @led_cdev: the led device to unreigister | ||
113 | * | ||
114 | * Unregisters a previously registered via led_classdev_register object. | ||
115 | */ | ||
116 | void led_classdev_unregister(struct led_classdev *led_cdev) | ||
117 | { | ||
118 | class_device_remove_file(led_cdev->class_dev, | ||
119 | &class_device_attr_brightness); | ||
120 | |||
121 | class_device_unregister(led_cdev->class_dev); | ||
122 | |||
123 | write_lock(&leds_list_lock); | ||
124 | list_del(&led_cdev->node); | ||
125 | write_unlock(&leds_list_lock); | ||
126 | } | ||
127 | EXPORT_SYMBOL_GPL(led_classdev_unregister); | ||
128 | |||
129 | static int __init leds_init(void) | ||
130 | { | ||
131 | leds_class = class_create(THIS_MODULE, "leds"); | ||
132 | if (IS_ERR(leds_class)) | ||
133 | return PTR_ERR(leds_class); | ||
134 | return 0; | ||
135 | } | ||
136 | |||
137 | static void __exit leds_exit(void) | ||
138 | { | ||
139 | class_destroy(leds_class); | ||
140 | } | ||
141 | |||
142 | subsys_initcall(leds_init); | ||
143 | module_exit(leds_exit); | ||
144 | |||
145 | MODULE_AUTHOR("John Lenz, Richard Purdie"); | ||
146 | MODULE_LICENSE("GPL"); | ||
147 | MODULE_DESCRIPTION("LED Class Interface"); | ||